Jannik Hansen had two goals for the Canucks, who sealed their seventh victory in eight games with four third-period goals in a span of 4½ minutes.
Sedin gave Vancouver some breathing room in the third after Schneider had to come in for Luongo, who was felled by a Gabriel Landeskog slap shot in the second period.
Sedin made it 3-0 when he outwaited Colorado goaltender Semyon Varlamov, then extended the lead to five by tapping home Alex Burrows' goalmouth pass.
It was the fifth career hat trick for Sedin, who opened the scoring on the Canucks' first shot of the game. He now has six goals in his last four games after an eight-game drought.
Luongo made 13 saves before Landeskog's shot appeared to catch him under his mask. Schneider, who blanked Colorado 3-0 on Nov. 13 after Luongo was injured, had to help his teammates stave off a two-man advantage soon after he entered.
Colorado had won three straight.
Vancouver was outplayed through the opening half of the first period but Sedin's wraparound beat the scrambling Varlamov, who made his seventh consecutive start ahead of veteran J.S. Giguere.
The Avalanche, who were coming off an eight-game homestand, then survived a five-minute power play in what became a game of attrition.
Kevin Porter received a major penalty and a game misconduct for kneeing Vancouver forward David Booth, who had to be assisted to the locker room and did not return. Booth, obtained in a trade earlier in the season with the Florida Panthers, couldn't put any weight on his right leg.
Schneider made 11 saves to get the Canucks to the third period with a two-goal lead. He was particularly sharp during a 44-second two-man advantage.
Hansen, promoted to the second line because of injuries, made it 2-0 with his third goal in as many games when he sent Kevin Bieksa's return pass past Varlamov. He picked up his ninth goal with a rising shot from the top of the face-off circle.
Alex Edler chased Varlamov at 9:40 of the third with a rising shot that caught the goaltender going down early.
NOTES: Paul Stastny was sidelined by a torso injury suffered in Colorado's 4-2 win over Detroit on Sunday. ... Canuck winger Chris Higgins was sidelined by a foot infection that has improved with medication. A similar infection cost him five games last season. Victor Oreskovich was called up from Chicago of the AHL to take Higgins' roster spot ... Vancouver winger Aaron Volpatti is expected to have surgery this week to repair a torn labrum in his left shoulder.